I am replacing the door knobs in my house with levers. My back door goes out into the attached garage and I am thinking I would replace the current deadbolt with one of the electronic ones that has a lighted key pad. I'm looking at Baldwin or Schlage. It's a metal door if that makes any difference. I assume I can just remove the old one and put in one of these new deadbolts without doing much to the door? Does anyone have one of these electronic deadbolts and what do you think? Do you constantly replace batteries? Appreciate any info.